Smith was to move under cover of night, up close to the enemy's works, and assault as soon as he could after daylight.

I believed then, and still believe, that Petersburg could have been easily captured at that time.

It only had about 2,500 men in the defences besides some irregular troops, consisting of citizens and employees in the city who took up arms in case of emergency.

Smith started as proposed, but his advance encountered a rebel force intrenched between City Point and their lines outside of Petersburg.
This position he carried, with some loss to the enemy; but there was so much delay that it was daylight before his troops really got off from there.

While there I informed General Butler that Hancock's corps would cross the river and move to Petersburg to support Smith in case the latter was successful, and that I could reinforce there more rapidly than Lee could reinforce from his position.
I returned down the river to where the troops of the Army of the Potomac now were, communicated to General Meade, in writing, the directions I had given to General Butler and directed him (Meade) to cross Hancock's corps over under cover of night, and push them forward in the morning to Petersburg; halting them, however, at a designated point until they could hear from Smith.